Chapter 17

Climatic Difficulties

Except in the heart of the continent, where evaporation rate greatly exceeds any possible supply of water, Australia has the best climate in the world for out-of-doors rose-growing. Dry-ness, sandy soil, and tropical conditions in the north are our only obstacles, except in fairly cold climates, such as parts of the South Island of New Zealand, southern Tasmania, and the towns near the Australian Alps, where minor difficulties may occur due to the low temperatures.

Roses In Cold Climates

Cold conditions as we know them consist of three or four cold months in midwinter, with light falls of snow. The ground becomes very wet, but there is no real freezing. After all, roses like heavy winter rains. Possibly, in rather dry winters, in any area, we should give extra water, though the hose is a poor substitute for rain. The blooming season is shorter than average in cold parts, but the disadvantages are less and the rewards greater than those of many oversea growers. When we receive reports of nurseries in England, Canada, the northern United States of America, Germany, and Denmark losing many thousands of plants because of low temperatures in winter, we know that they are, of course, mostly young plants with a large proportion of young wood, but gardeners lose many established plants at the same time. The Pernetianas are most subject to loss by freezing. Any rose plant that, after winter pruning, consists entirely of young wood (usually watershoots) is apt to be cold-tender also.

In the cold parts of the United States of America many rose-growers protect their plants for over six months each year by elaborate and costly methods. Bushes are cut down to less than one foot and then completely covered with straw or brambles and with earth from a reserve pile kept for that purpose. Climbers are untied from their supports and soil is hilled round their bases, while the canes are laid flat on the ground and covered similarly to the bushes. Standards need to be bent right over into a horizontal position. A trench is dug along one side of them, cutting the roots; a spade is driven into the ground about a foot from the base of the trunk on the other side, the plant is untied from its stake and then gently turned down to the ground so that a half or a third of the head of the standard is below soil surface level. The trunk is pegged firmly and the whole plant is covered with straw, dead leaves, burlap, and soil.

These plants remain covered for from four to seven months according to the season and the climate of the particular area. The cold is so severe that even with all this care many branches are killed. We have no difficulties to compare with these, and mention of them is made only to stress, firstly, how favourable is our climate, and secondly, how ardent are these men in their determination to grow roses.

In our so-called cold areas the only necessary precaution is the selection of varieties that will open satisfactorily during six months of the year under outdoor conditions. Winter pruning should be done a little later than usual and summer trimming earlier than elsewhere. Planting should be done in late July or early August, and possibly the union of stock and scion is best placed below soil level.

So far, Tasmania, our coldest State, has no National Rose Society. The advent of such an organization would give a great impetus to rose-growing there. Roses are grown in large numbers in home gardens and, as elsewhere, are the most popular of all flowers. There are several branches of the National Rose Society of New Zealand in the South Island, as well as some well-known public rose gardens.

Roses In Sub-Tropical Climates

Sydney's gardens contain probably more roses than those in any other city of Australia, but Queensland must eventually assert herself in the rose sphere, especially the south-eastern half of the State. In Brisbane and surrounding parts roses may be successfully budded or planted on any day of the year, and blooms can be gathered in profusion at any time. The plants are never at rest; growth is quick and rampant. The absence of a true rest period seems to cause many plants to lose their virility within a few years. The Tea Roses do wonderfully well. They are often regarded as old-fashioned roses and are not popular in some climates, but they show their full beauty in warm climates. Pernetianas and Hybrid Perpetuals, except Frau Karl Druschki, do not live long. Climbing Hybrid Teas do very well. Black spot is often troublesome.

Roses In Tropical Climates

Going still farther into the tropics, heat and humidity increase. One would expect this to be inimical to roses and especially to Pernetianas. The far northern area, with Townsville as its centre, provides a distinct contradiction. Dwarf plants of Dame Edith Helen on R. multiflora understock commonly grow six feet high and nearly as much across. Their blooms are so outstanding that the variety is debarred at local shows from all classes except those specially provided for it. Many full-bodied Pernetianas fail in Brisbane and yet flourish round Townsville. This is almost certainly due to the fact that Townsville is in a comparatively dry area in the otherwise wet coastal strip. There is an average annual rainfall of forty-seven inches, but thirty-seven of these fall in the four-month period from mid-December to mid-April. Roses thrive around Bundaberg. Most rose-breeding is directed to meet the requirements of the temperate climates. Tropical conditions are rarely considered, yet roses of very high quality can be grown under them. The varieties chosen must be full-bodied and, usually, not of the Pernetiana type, for they will seldom live more than three or four years. Some of them give excellent results if grown as annuals. Thin-bodied roses of less than twenty-five petals are useless, for they become full-blown too quickly. All blooms cut for home decoration must be gathered in a rather immature state, and no time must be lost in placing them in water.

One of the greatest factors in successful rose-growing in coastal Queensland is heavy feeding with manures rich in potassium and phosphorus. Bone-meal with either compost or cow manure and wood ashes is probably best. Nitrogen should be given sparingly.

Roses In Hot, Dry Climates

In many inland parts of Australia roses will grow well, but those with a small number of petals give blooms of poor lasting quality. Ample supplies of good water are essential; artesian water is often harmful. Roses grown without regular artificial watering during the summer will still give a good spring blooming and probably a light autumn crop. Heavy feeding or excessive watering will lead to soft sappy growth that will shrivel badly in the hot, dry summer weather.

Of course, if the grower is ambitious as an exhibitor, both food and water must be given freely at appropriate times, but for the home gardener who wishes to have roses for home and garden decoration only, success can be achieved by quite simple cultivation even in parts as dry as the Mallee.

In the areas of low rainfall and high summer temperatures, dwarf roses are best, for they have no trunk to suffer from sunburn and the plant itself shades the area of ground in which the roots are growing.

One of the greatest problems is the wide cracks that open in the soil in summer. This can be avoided only by greatly increasing the humus content of the garden. Careful preliminary preparation of the beds is necessary, followed by the use of compost, vegetable matter, cow manure, or horse manure containing large quantities of straw. Every available particle of organic matter must be most carefully saved and used as compost material. All household water should be poured round rose bushes, soaking them in rotation rather than sprinkling several at a time. Ironically, it is in these areas where the need for water and these organic foods and soil-conditioning agencies is greatest that their supply is poorest. There are no lawn clippings, for lawns are impracticable, being killed by summer heat; household vegetables are often brought from distant parts, and, to reduce weight in transport, their surplus foliage is left behind. Water conservation schemes will greatly reduce these problems. There is usually a lush growth of grass and weeds in spring. A good gardener will use this vegetation before it seeds to make compost or even hay for mulching. It is better, though, to grow a green crop in an adjoining area during the late winter and early spring. Animal manures are usually available in sufficient quantities; sawdust is useful.

FONTANELLE, an outstanding yellow rose. Plate 36 GRAND'MERE JENNY. Its longer stems and greater freedom of blooming make this great Hybrid Tea rose better for garden and home decoration than its parent, Mme A. Meilland. Plate 37

Growing Roses In Sandy Soils

The greatest prerequisite for successful rose culture in sandy soils is careful preparation of the beds. This has been fully dealt with in Chapter 10. Rose-growing in sandy soils need never be regarded as difficult, let alone impossible, despite frequent statements to that effect. As in all other types of soil, the roses must not be manured in the .first few months after planting, but a mulch of straw or leaves to a depth of two or three inches will be helpful. It will make both the soil temperature and the soil moisture more equable. For this purpose it is inadvisable to use fresh vegetable matter, such as lawn clippings, for they ferment when in thick layers. If sawdust is used it should be spread sparingly but at intervals of a few weeks.

In the late summer, compost or animal manure with wood ashes, straw, leaves, and bone-meal should be added. Organic matter, especially decomposed vegetable waste material, should be given unsparingly. Sandy soils are most common in coastal districts, where seaweed is often available. However, it is illegal to collect it from beaches in some municipalities without a permit.

Sandy soils need watering at frequent intervals, for the coarse soil particles allow rapid drying by both evaporation and drainage. Heavy soakings will last very little longer than medium applications, and will do great disservice by washing away precious plant foods.

Successful rose-growing in sandy soils depends largely on the selection of the understock. R. fortuniana and R. multi-flora are very well adapted to the circumstances, each having extensive and densely massed fibrous root systems capable of seizing all available food.

No soil is more sandy than that of metropolitan Perth or some of Sydney's suburbs. The two stocks named seem equally successful in these areas, and those of us who have been fortunate enough to see well-grown plants and blooms in both cities need have no further doubts as to the possibilities of rose-growing in soil that was almost pure sand before the rose enthusiast set about preparing his garden. Not only have growers in these parts and in coastal Queensland disproved the old idea that roses need heavy clay, but they enjoy glorious displays of blooms for at least nine and, in many parts, twelve months of the year.

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